Diagnostics Code P0642 - Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum
Ford Focus Forum
HomeContact UsAbout UsGalleryDiscussion ForumsMarketplace


Go Back   Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum > Ford Focus Tech Discussions > General Technical Chat

General Technical Chat This section is for technical discussions relating to general maintenance, electrical issues, engine trouble, and recalls.

Search This Forum | Image Search | Advanced Search    
FocusFest

Reply
 
LinkBack Thread Tools Display Modes
Old 01-09-2017, 02:54 PM   #1
Focus Rookie
 
Join Date: Jan 2017
Fan#: 338626
Location: Pleasant Prairie, WI
What I Drive: 2010 Red Focus SEL

Posts: 3
Points 14, Level 1
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Level Up 27% Completed
Level up: 27% Level up: 27% Level up: 27%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 1 mscotese@aol.com Good Standing Member
Buy-Sell-Trade Rating: (0)
Diagnostics Code P0642

Hi my 2010 Focus engine light came on with code P0642 Sensor A Low Voltage. Also started running rough when the same time the engine light came on. I can find very little info on this on Google. Any advice please? 178,000 miles, automatic has been a perfect until now. I see some saying it needs and new ECM. My dealer wants $625 for the part plus $150 to program it. He says he can't reprogram a used on which I can find for $30 locally. As I am not confident that the ECM is the problem I am hesitant to proceed with replacing it. Thanks, Mike


mscotese@aol.com is offline  
    Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 01-10-2017, 11:41 PM   #2
Trump 2016
 
pasta's Avatar
 
Join Date: Jan 2009
Fan#: 62350
Location: queens, NY
What I Drive: 2003 eap svt

Posts: 6,808
Points 20,442, Level 90
Points: 20,442, Level: 90 Points: 20,442, Level: 90 Points: 20,442, Level: 90
Level Up 19% Completed
Level up: 19% Level up: 19% Level up: 19%
Forum Activity 99%
Activity: 99% Activity: 99% Activity: 99%
FF Reputation: 10 pasta Great Standing Member
Buy-Sell-Trade Rating: (48)
Get a second opinion.
pasta is offline  
    Reply With Quote Quick reply to this message
Old 01-11-2017, 07:52 AM   #3
FF Affiliate
 
1turbofocus's Avatar
 
Join Date: Oct 2003
Fan#: 1123
Location: Belmont, NC
What I Drive: 2000 ZX3 / 2002 SVT Turbocharged

Posts: 26,718
Points 67,612, Level 100
Points: 67,612, Level: 100 Points: 67,612, Level: 100 Points: 67,612, Level: 100
Level Up 0% Completed
Level up: 0% Level up: 0% Level up: 0%
Forum Activity 99%
Activity: 99% Activity: 99% Activity: 99%
FF Reputation: 158 1turbofocus Excellent Standing Member 1turbofocus Excellent Standing Member
Buy-Sell-Trade Rating: (29)
https://www.obd-codes.com/p0642 this should help

Any dealer that wont program a use ECU/PCM is just trying to screw you they can program a used one just as easy as a new one ,

The link should answer some questions

Tom
__________________
Focus-Power: Your #1 Source for Ford Focus Speed, Tuning & Performance!

Customer Support
AIM: hpdyno
Email:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Phone: 704-249-3745
Site:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


Elder 1turbofocus
1turbofocus is online now  
    Reply With Quote Quick reply to this message
 
Old 01-11-2017, 08:15 AM   #4
Focus Rookie
 
Join Date: Jan 2017
Fan#: 338626
Location: Pleasant Prairie, WI
What I Drive: 2010 Red Focus SEL

Posts: 3
Points 14, Level 1
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Level Up 27% Completed
Level up: 27% Level up: 27% Level up: 27%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 1 mscotese@aol.com Good Standing Member
Buy-Sell-Trade Rating: (0)
Thanks that link was helpful. I ordered a new throttle body and am assuming that the Sensor A with the low voltage is in there. It runs like the ECU does not know the position of the throttle plate and it seems lots of people have had trouble with their throttle bodies based on the forum posts. Also have a used ECM ($50) coming with all numbers the same as mine except the last three digits of the serial number which makes sense to me.
mscotese@aol.com is offline  
    Reply With Quote Quick reply to this message
Old 01-11-2017, 09:55 AM   #5
FF Affiliate
 
1turbofocus's Avatar
 
Join Date: Oct 2003
Fan#: 1123
Location: Belmont, NC
What I Drive: 2000 ZX3 / 2002 SVT Turbocharged

Posts: 26,718
Points 67,612, Level 100
Points: 67,612, Level: 100 Points: 67,612, Level: 100 Points: 67,612, Level: 100
Level Up 0% Completed
Level up: 0% Level up: 0% Level up: 0%
Forum Activity 99%
Activity: 99% Activity: 99% Activity: 99%
FF Reputation: 158 1turbofocus Excellent Standing Member 1turbofocus Excellent Standing Member
Buy-Sell-Trade Rating: (29)
ECU goes by strategy , ECU code and the Ford part # , most salvage yards use the Ford ECU/PCM codes like 8S4A-ALB , this is the # you want to make sure matches

I dont feel you have a bad ECU/PCM tho

Tom
__________________
Focus-Power: Your #1 Source for Ford Focus Speed, Tuning & Performance!

Customer Support
AIM: hpdyno
Email:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Phone: 704-249-3745
Site:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


Elder 1turbofocus
1turbofocus is online now  
    Reply With Quote Quick reply to this message
Old 02-10-2017, 10:57 AM   #6
Focus Rookie
 
Join Date: Jan 2017
Fan#: 338626
Location: Pleasant Prairie, WI
What I Drive: 2010 Red Focus SEL

Posts: 3
Points 14, Level 1
Points: 14, Level: 1 Points: 14, Level: 1 Points: 14, Level: 1
Level Up 27% Completed
Level up: 27% Level up: 27% Level up: 27%
Forum Activity 1%
Activity: 1% Activity: 1% Activity: 1%
FF Reputation: 1 mscotese@aol.com Good Standing Member
Buy-Sell-Trade Rating: (0)
Fixed it with a new intake runner (or tumbler) position sensor from eBay for $93.20.

This sensor 8S4Z-9P471-A is referred to on eBay as a temperature sensor and as a pressure sensor but it is actually a rotary position sensor. It fits the square shaft running through the intake manifold and gives the shaft position to the ECU.

Mine failed on the coldest day of the year at -2 degrees F but not sure that is relevant.

Anyhow just wanted to complete this posting with the identified fix. Car has run great for two weeks now with no dash light coming on.

Thanks for your input, Mike
mscotese@aol.com is offline  
    Reply With Quote Quick reply to this message
Old 02-15-2017, 10:50 AM   #7
Focus Addict
 
Join Date: Mar 2010
Fan#: 73790
Location: Syracuse, NY
What I Drive: 2011 Focus SE 5 Speed

Posts: 1,232
Points 2,606, Level 31
Points: 2,606, Level: 31 Points: 2,606, Level: 31 Points: 2,606, Level: 31
Level Up 4% Completed
Level up: 4% Level up: 4% Level up: 4%
Forum Activity 3%
Activity: 3% Activity: 3% Activity: 3%
FF Reputation: 5 Miller88 Good Standing Member
Buy-Sell-Trade Rating: (0)
Wow - good fix!

How did you find the sensor was bad?
__________________
2011 Focus SE 5 Speed.
Miller88 is offline  
    Reply With Quote Quick reply to this message
Reply

Bookmarks & Social Networks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
What I Drive
Year, color, and model of your car. Example: 2003 Pitch Black ZX3
Name
Your real name.
City
State
Country
Insurance
Please select your insurance company (Optional)

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 02:31 PM.


Copyright 2002-2015 FocusFanatics.com. All Rights Reserved : Privacy Policy : Advertise Information

Focus Fanatics Ford Focus Forum offers many fun ways for you to engage with other Ford Focus Owners from across the world. Whether it be about the aftermarket performance modifications, technical how-to's, European tuned suspension or awesome fuel economy similar to the Mazda CX-3, Audi S3, Mazda MX-5 Miata and Acura TLX. You can find all Ford Focus, Focus ST and Focus RS related information here. Join our Ford Focus discussion forums and chat with local Focus enthusiasts in your area. If you own other makes have a look at Challenger Hellcat Forum, Charger Hellcat Forum, Cadillac ATS-V Forum, Cadillac CTS-V Forum, Lexus RC-F Forum, Lexus GS-F Forum, Mercedes GLA Forum, Mercedes GLE Forum and Volvo XC90 Forum.




 

Search Engine Optimization by vBSEO 3.6.1